debris) and the ground- or space-based laser evaporation of debris surface material to deorbit small debris. The sweeper scheme seems technically difficult, demonstrably inefficient, hazardous to functional spacecraft, and risks producing more small objects than it eliminates. The laser concept, although interesting, requires costly new technology, and its feasibility has not yet been proven. In general, there is currently no technology able to remove small debris efficiently, and any foreseeable schemes look very costly.

FINDINGS

Finding 1: The future debris hazard can be significantly ameliorated without exorbitant costs by ending or sharply reducing the number of breakups of spacecraft and rocket bodies and, to a lesser extent, by reducing the amount of mission-related debris released in spacecraft deployment and operations. Methods to achieve both these goals exist, are relatively inexpensive, and have been proven in orbit. While implementing these methods will reduce the total number of objects in orbit, it will not, however, significantly reduce the total mass of objects in orbit.

Finding 2: Deorbiting or accelerating the orbital decay of spacecraft and rocket bodies at the end of their functional lifetimes can reduce the total amount of mass and cross-sectional area in orbit. The difficulty and cost of such maneuvers vary depending on the initial orbit, the capabilities of the space vehicle involved, and the desired reduction in orbital lifetime. In general, significant reductions in orbital lifetime can be achieved with much less fuel than deorbiting would require.

Finding 3: Reorbiting spacecraft and rocket bodies into disposal orbits can reduce the debris hazard in their original orbit, but it is not a permanent solution since the debris remains in Earth orbit. Decisions to use a disposal orbit must balance the reduction in the long-term hazard to functional spacecraft against the cost of the maneuver, including the cost of carrying the required fuel and/or the need for premature shutdown. Disposal orbits are not a useful alternative within LEO; opinion within both the committee and the space debris community is divided as to whether they should be used by all spacecraft and rocket bodies in GEO.

Finding 4: The active removal of debris will not be an economical means of reducing the debris hazard in the foreseeable future. Design of future spacecraft and launch vehicles for autonomous deorbiting, lifetime reduction, or reorbiting is a far more economical means of reducing the collision hazard.



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